Discoveries (theoretical novelties) in c70 Morphy defence: Yanish gambit deferred (Schliemann defense deferred, Schliemann gambit deferred, Jaenisch gambit deferred, c70 gambit variation), changing appraisal of its very important systems, are present in this investigation.

Summary of analysis (author's novelties are marked by symbol "AN")

1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 f5

Paragraph 1: 5.Bc6!

White has an advantage. (This is a new appraisal of variant 5.Bc6.) Here is a main way: 5...dc 6.ef AN e4 7.Qe2 Qe7 8.Nd4 Qe5 9.c3!?AN; 9.Ne6!?AN.

It’s a brief text only! The full text of this paragraph coincides completely (including all symbols “AN”) with paragraph 2 (3...f5 4.Bc6!) of my C63-article (C63 Yanish [Schliemann Defence] Discoveries)!

It should be noted, that pawn’s position a6 (instead of a7 in C63) doesn’t increase black’s possibilities in almost all cases. It increases black’s possibilities a little in rare cases, but it saves black nowhere.

My C63-article was published very long ago, and in that time I didn’t see a necessity to indicate the completely analogous change of appraisal of C70-variant (3...a6 4.Ba4 f5 5.Bc6), because the change of this appraisal is a trivial consequence from my C63-article. A lot of high-qualified chess commentators of my C63-article, of course, marked this consequence, but I was astonished, that a lot of other high-qualified chess commentators of my C63-article didn’t mark this consequence.

Author: Y.Bukayev